Ulva flexuosa (Ulvaceae, Chlorophyta) inhabiting inland aquatic ecosystems: molecular, morphological and ecological discrimination of subspecies

In this paper, we examine Ulva in inland aquatic ecosystems to determine relationships between the chemical parameters of the water and the Ulva taxa present. Two groups of samples of freshwater Ulva were selected from: (i) habitats with high salinity levels, and (ii) habitats with fresh or slightly saline waters.

We showed that these two groups of Ulva , which occupy distinct habitats, represent two separate taxa. The first group represents Ulva flexuosa subsp. pilifera (Kützing) M.J. Wynne, which is very common and regularly encountered in fresh waters, but is equally well represented in slightly saline waters. The second is U. flexuosa subsp. paradoxa (C. Agardh) M.J. Wynne, which is less common, preferring mainly salt-wedge saline waters.